Comparison between predilution and postdilution continuous renal replacement therapy (CRRT) for patients with MODS

Abstract

Objective To comparie the effects of pre-dilution with post-dilution continuous renal replacement therapy (CRRT) for patients with MODS. Method Thirty-two MODS patients admitted to ICU (Intensive Care Unit ) were randomized and treated with different modes of CRRT. The results of creatinine clearance, acid-base equilibrium, haemodynamic variables before and post therapy were recorded.The maximal pre-filter pressure, the duration of filter unworn out and mortality of patients treated with different modes of CRRT were also recorded. Results Seventeen patients were treated with pre-dilution mode of CRRT and 15 patients treated with post-dilution mode of CRRT. After 24 hours of pre- and postdilution modes of CRRT, the net increase in Ccr (namely the rate of replacement creatinine clearance) were (15.6±4.6) vs. (22.7 ±4. 1) mL/min respectively (P＜0.01); after 48-hour, they were (14.9±3.3)vs. ( 18. 9 ±2. 3) mL/min (p ＜0. 05) . Both dilution modes could improve the blood PH、 HCO3- and BE( P ＜ 0. 05 ) without significant differences between two groups after CRRT therapy ( P ＞ 0. 05 ) . The MAP of patients treated with pre-dilution modes of CRRT therapy for 24 hours and the MAP of patients before therapy were 69. 2 ± 4. 6 and 56. 7 + 9. 1 mmHg respectively ( P ＜ 0. 05 ), and dosage of dopamine used in patients before CRRT therapy and that after CRRT for 24 hours were ( 11.20 +3.45 ) vs (6. 12 +3.41 ) μg ·kg-1 min -1(P＜0.05).The maximal pre-filter pressures of pre-and post-dilution modes were (82.23+9.11) cm H2O, (110.56 +28. 14) cmH2O respectively (P＜0.05), and the durations of lasting effect of filter used in two modes of CRRT were ( 39 + 28. 12 ) vs. ( 25 + 14. 45 ) h respectively ( P ＜0. 05) . Both dilution modes could improve APACHE Scores. There were no significant differences in APACHE Scores and mortalities between two groups after CRRT therapy. Conclusions Post-dilution mode of CRRT has higher filtration rate, but have higher maximal pre-filter pressure and shorter longevity of filter.Pre-dilution mode of CRRT has better effect on improving hemodynamics, reducing usage of vasopressor.Both modes of CRRT can correct acid base equilibrium disorder rapidly. There are no differences in the results of blood gas analysis improved、 APACHE scores and mortality between the two groups. Key words: Continuous renal replacement therapy (CRRT); Multiple organs dysfunction syndrome (MODS); Predilution; Postdilution